<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="app">
        {{ message }}
        <br>
        {{ count }}
        <br>
        <button type="button" @click="counter">+</button>
    </div>
    <script src="https://unpkg.com/vue@next"></script>
    <script>
        // import { ref } from 'Vue'
        const app = Vue.createApp({
            setup() {
                let message = Vue.ref("hello vue setup")
                let count = Vue.ref(0)

                const counter = () => {
                    count.value++;
                    console.log(count.value);
                }

                
                Vue.onMounted(() => {
                    console.log("onMounted => hahaha")
                })
                
                return {
                    message,
                    count,
                    counter
                }
            }
        })
        app.mount("#app")
    </script>
</body>

</html>